Tower for television aerials



Jan. 4, 1955 c. l.. ALLswoRTH ETAL 2,698,873

TOWER FOR TELEVISION AERIALS Filed June 20, 1950 HAOLD SHOUK Y B@My/zam? a?? United States Patent Olitiee 'Patented Jan. 4, 1955 TOWERFOR TELEVISION AERIALS Clifton L. Allsworth, Montara, and Harold A.Shook, Pascadero, Calif.

Application June 20, 1950, Serial No. 169,236

2 Claims. (Cl. 17445) This invention relates to a tower for a televisionaerial and has for its principal object the provision of a tower that iseconomical to make and to install and that is compact and rugged.

The installation of aerials for television sets in certainlocalitiespresents a very difcult problem for the reason that the band wherereception is best may be relatively far above the ground and at acritical level. The level where receptionl is best may be considerablyabove the top of the house in which the receiver is located, and it maybe within a narrow band of a few feet or less in vertical width.

One of the objects of the present invention is the provision of acompact tower of relatively few partsthat is economical to make and toerect and that is adapted to carry the aerial to exactly the desiredlevel where it can be rigidly held.

Heretofore, where a tower is required for the aerial, it has been thepractice to build such tower along conventional structural lines, usinga lattice work of structural steel braces in much the same manner as thetowers or masts of the ordinary radio or wireless sending station areconstructed, except on a smaller scale. The expense and time requiredfor constructing such a tower are prohibitive in most instances, and theprospective users of television sets either tolerate inferior receptionor forego the purchase of a television set until the time when theproblem of installing an aerial capable of effecting proper reception isovercome.

Even when the conventional towers are installed, the difficulty existsof determining where the tower is to end in order to position the aerialat the desired level. The tower may be designed for supporting an aerialat say a thirty foot level but it may be found, after erection, that theproper level is about twenty feet. Or it may be found that the desiredlevel is about forty feet after a twenty or thirty foot tower iserected. In many such instances, the builders complete the toweraccording to the original estimate, with the result that the userobtains inferior reception in the belief that better reception isimpossible in his particular locality.

With the present invention, the aerial may be easily positioned by asingle person at exactly the correct level,

which may be quite high above the ground. Also, the

elevation of the aerial rnay be easily changed to meet changingconditions of reception without removing or adding parts.

In the drawings, Fig. l is a reduced elevational view of the tower, thestay wires being broken in length.

Fig. 2 is an enlarged perspective view of the tower, sections beingremoved to accommodate the view to the sheet and the elements being incross section where the sections are removed. The stay wires are brokenaway and the aerial itself is not shown.

The tower of Fig. 2 is collapsed, whereas that of Fig. l is extended.

Fig. 3 is an enlarged cross sectional view taken about on line 3 3 ofFig. l.

In detail, the invention as illustrated in the drawings comprises a base1 that may be an inverted channel strip of structural steel, or that maybe formed from a pair of angle iron strips welded together, asindicated. This base is adapted to be imbedded in the ground or in aconcrete base (not shown). In actual practice, it has been found that abase 1 of about a foot and a half or two feet in length and of aboutfour inches in width is satisfactory for the sizes of other parts thatwill later be described where the tower, when at its fullest height isabout forty to fifty feet in height.

Welded to base 1 centrally between its ends is a half clamp 2 havingwings 3 at its ends for the passage of bolts 4. This half clamp 2 has alaterally curved central portion 5 that is adapted to partially encirclethe lower end of a vertical cylindrical and tubular lower ost 6. 1 p Theother half 7 of the clamp is complementary to half 2 and has wings 8apertured for passage of bolts 4. The half -7 is free for removal fromthe base and for movement toward Vhalf 2.

Upon setting the lower end of the lower post 6 on base 1 and positionedin thecurved recess formed by central portion 5 of the half 2 of theclamp, the said lower end will be rigidly secured to said base bybolting the half 7 to half 2.

The lower post 6 may be of ordinary two inch iron water pipe and may beforty or more feet in length, although it is obvious that the pipe maybe of any desired metal or alloy. An upper post 10 is telescopicallyslidable through the open upper end of post 6. Post 10 may be ofstandard inch and a quarter iron pipe and the llength of this upper postmay be twenty feet or more.

The standard length of each post 6, 10 is about twenty or twenty-onefeet, but the present invention is not intended to be restricted to anyprecise length.

A collar or sleeve 11 is secured to the lower end of the upper post iti,and this sleeve will function as a bearing for spacing the post 10within post 6.

The upper end of the lower post 6 may have a half clamp 12 rigidlysecured thereto, which half clamp is identical with the half clamp 2,except that the central laterally opening recess 13 is smaller forreceiving the smaller post 10. A half clamp 14 complementary to halfclamp 12 is releasably bolted by bolts 1S to half clamp 12 for clampingthe lower or inner post 10 at any desired degree of extension upwardlyfrom post 6, and for supporting the upper post by the lower post 6 atthe upper end of the latter.

The said half clamp 12 may be carried on a sleeve 16 that is threadedlysecured to the upper end of post 6.

Sleeve 16 also has a pair of vertically spaced rings 17, 18 securedthereto below the above mentioned clamp elements. Between said rings 17,18 is a ring 19 that is rotatable about the axis of the post 6. Thisring 19 has outwardly projecting eye members 20 secured thereto at threeequally spaced points for attachment of stay cables or wires 21 thereto.These cables may be secured at their lower ends to the ground by deadmensunk in the ground in the same manner as telephone pole stay wires areheld, or they may be secured to posts held in the ground or in any othersuitable manner for holding the post upright, such as by attachment ofbuildings, etc.

A vertical slot 22 is formed in the upper end of lower post 6 at a pointspaced several inches below the sleeve 16. A pulley 23 extends into saidslot, said pulley being rotatably supported on the lower post by a shaftthat, in turn, is supported in bearings 24 on the post at opposite sidesof the pulley.

A cable 25 extends over pulley 23 (which pulley is preferably formedwith a peripheral outwardly opening channel for the cable), and into thespace between the upper post 10 and the lower post 6. This cable issecured at one end to the lower end of the upper post 10 by a cableclamp or by any other suitable means, and at its other end it is securedto a windlass 26 that is positioned outside post 6 and below pulley 23.

The windlass 26 is preferably supported for rotation in bracket arms 27.These arms 27 are at the ends of a half clamp 28, the latter beingreleasably secured to the post 6 by a second half clamp 29. The halves2S, 29 extend across opposite sides of the post 6 and are boltedtogether by bolts 30. While the windlass 26 may be positioned at thelower end of post 6 it is preferably positioned adjacent the upper endof said post so that an operator in a position on post 6 to tightenclamp halves 12, 13 may operate the windlass without changing hisposition.

A handle 31 is on the windlass for operation of the same, and a pawl 32is pivotally secured to one of the bracket arins" 27 for" engaging theteeth of a ratchet wheel 33 that; in turn, is secured on the wlndlassshatt tor pre-V venting reverse rotation or' the windlass, except whenthe pawl is litted.

The lower post 6 isprovided with radially projecting rods 35 providing aladder to'r climbing the lower post to a point where the clamp halves12, 14 can be tightened, and from which point the windlass can beoperated. The rods 35 are preterably at opposite sides ot' tne lowerpost in staggered relationship, except for the top two rods, which areopposite each other, as seen in Fig. 1.

The upper post l0 is provided at its upper end with a`- sleeve 4u thatis the same as sleeve 16 except that it is smaller for the smaller post10. bleeve 4v 1s prererably threaded on the upper e'nd of post 1u andhas vertically spaced rings 41,- 4Z secured thereto for holding a loosering 43 therebetween, which ring 43 is adapted to rotate on the axis or'the upper post.

Ring 43 has three equally spaced outwardly projecting eye members 44secured thereto for stay wires 45 that, in turn, are adapted to besecured at their lower ends to the ground or deadmen, or to othersuitable holding means tor holding the post upright. p

Secured to the upper end of the sleeve 40 is a halt` clamp 46 that isidentical with the half clamp 12, except that it is smaller. Acomplementarily formed halll clamp 4l is adapted to be removably securedby bolts 43 to the half clamp 46 forl securing the post 49 of aconventional television aerial 50 thereto. 'the post 4@ istelescopically slidable into the upper end of the upper post 1t) and maybe or' any desired length, but preferably not longer than post 1l).

ln many instances', it is desirable to secure the conductor leading fromthe television aerial to an electrical insulator on the upper postbefore leading the conductor to the building in which the receiving setis located. Such an insulator is provided in the form of a strip "51 ofrelatively rigid electrical insulation material. This strip may beclamped to the upper end of the upper post 1u by a U-'clar'np 52 that inturn carries a spacer 53 (Fig. i cal tubular lower post, a verticaltubular 'upper post tele- 3) that secures the strip 51 to the U-clampand at the same time spaces the strip a suicient distance from the postit) to enable the lower end of the strip to slide over the rings andclamp elements carried by the upper end of the lower post 6 should theupper post be only partially extended. A U-clamp 54 is adapted toreleasably secure the lower end of the strip 51 Ato post 6 after post 10 is in its iinally adjusted position, in the `event the post 10projects upwardly from post 6 a sufficient distance to carry the lowerend of strip 51 to a point above the upper end of post 6 (Fig. 1) or inthe event a relatively short strip 51 is all that is required.

The width of strip 51 is such as not vto interfere with the stay wires,or cables 21 although it is obvious that the ring `to which the saidcables are connected may be rotated about post 6 to the most desirableposition. Pref- 'erably the strip 51 is of a material that may receivestaples for stapling the conductor thereto. Wood has been found to besatisfactory.`

The posts 6, 10 and the entire assembly may be carried in collapsedposition to the site where the tower is to be erected, and when the base1 is set in the desired position the stay cables 21 may be anchored tohold the collapsed post assembly upright. The operator may next climbthe post 6 to a point adjacent the windlass 26. The receiving set maythen be connected with the aerial in the conventional manner, and theoperator from his position at the upper end of the lower post 6 willcommence to actuate the windlass for elevating the upper post, and theaerial thereon. When tests on the receiver show that the aerial hasreached the height or' maximum etticiency the clamp haltl 14 istightened and the stay wires 4: are anchored. The conductor trom theaerial to the house is secured to the lower end of the insulation stripand the said strip is' secured in place to either the upper or lowerpost. 'this completes the job, and the complete installation can beeh'ected in a small fraction o1' me time required to set up the ordinarytower of structural steel members and at a small fraction of the cost.Should the operator fully extend the post 6 and still greater elevationis required, the upper post may be lowered to the point where theoperator may loosen the clamp halt 4'/ and elevate the aerial post. Theaerial post may then be secured to the upper post in its extendedposition, and thereafter the said upper post may be elevated the desireddistance in the manner described, More posts may be employed but usuallythe number as illustrated and as described is adequate.

It is understood that the invention is not to be limited to the precisestructure above described in detail, inasmuch as the structure so shownand described is merely the preferred structure.

We claim: n

1. A tower for a television aerial comprising a vertical tubular lowerpost, a vertical tubular upper post telescopically slidable through theupper end of said lower post from a collapsed position substantiallywholly enclosed Within said lower post to any desired degree ofelevation projecting from said upper end, a strip of electricalinsulation material secured -to said upper post and alongside the sameand movable therewith over the outer side of said lower postlongitudinally of the latter, means on the upper end oi said upper postfor securing a television aerial thereto, said strip of insulationmaterial being adapted for securing the conductor for said aerialthereto.

2. A tower for a television aerial comprising a vertiscopically slidablethrough the upper end oi. said lower post from a collapsed positionsubstantially Wholly enclosed within said lower post to any desireddegree of elevation projecting from said upper end, a strip ofelectrical insulation material secured to saidupper post and alongsidethe same and movable therewith over the outer side of said lowerpOS'L'lOngitudinally of the latter, means on the upper end of said u perpost for securing a television aerial thereto, said strip of insulationmaterial being adapted for securing the conductor for said aerialthereto, and means for releasably securing said strip to said lowerpost.

References Cited. in the `le of this patent UNTED STATES PATENTS 221,076Lathrop Oct. 28, 1897 657,732 Francis Sept. 1l, 1900 963,237 Milton July5, 1910 l,2l3,242 Gverly et al. Ian. 23, 1917 1,795,747 Villen Mul". l0,1931. 2,063,303 Evans Dec. 8, i936 y2,337,719 flueglin Dec. 28, 19432,369,533 Cohen Feb. 13, 1945 2,583,210 Edwards Jan. 22, i952 2,642,754De Conti lune 2.3, 1953

